Stable Semiconducting Ink Based on a Polypyrrole/Carbon-Quantum-Dot Aqueous Colloidal Suspension: A Potential Sensor for Volatile Organics Present in Food

Water dispersible conducting carbon quantum dots (CQDs) have been modified with PPy through a unique surface confined auto-catalytic process. Viscoelastic and electronic characteristics of the concentrated CQD-PPy aqueous suspension confirmed semiconducting ink-like behavior. The ink forms stable impression on paper, glass and fabric. CQD-PPy ink coated substrates respond selectively towards different flavors (VOCs) originating in packaged food items.